This invention relates to a pattern forming method and a pattern forming apparatus, and more particularly to a method for forming a pattern in liquid and an apparatus for carrying out the method.
Usually, the photolithographic method is widely used for pattern formation. For example, according to a customary used pattern forming method for an integrated circuit, a photosensitive composition is coated over a substrate such as silicon, and then exposed to an ultraviolet light or X-ray through a suitable photomask to transmute only the exposed photosensitive composition. Thereafter, a predetermined part of the substrate is subject to development to expose the part and then subjected to necessary later processes such as etching, deposition and so on. Since an object to be processed for fabricating an integrated circuit is of a minute dimension from submicron to micron, the influence of dust is considerable in whole processes. In order to attain no defect, dust removal and its control are essential requirements. The so-called photo-processes such as exposure and development makes no exception. Further, in the exposition step, the photomask which absorbs the irradiation energy suffers from thermal expansion, to cause a difficulty of control of the dimensional accuracy in the process.